The use of composites, known by the English acronym FRP (Fibre Reinforced Polymer) is known for structural reinforcement in engineering and architecture, applied to civil and industrial buildings and infrastructures such as bridges, viaducts and galleries. An example of this application is given in the patent No. IT1298946 which discloses a consolidation method consisting of the application of a single layer of composite substance on a structural element to be reinforced. The composite is obtained by depositing a layer of resin which adheres to the structural element and whereon is laid a unidirectional or multi-axial fabric, dry pre-impregnated, e.g. carbon fibre, glass fibre or aramid fibre. Lastly, on the impregnated fabric is applied additional resin to complete the impregnation of the fabric and assure its final gluing.
While the known methods briefly described above allow to reinforce the buildings statically even after a partial structural collapse, they are not able to perform a preventive action. In other words, such methods cannot assure the absorption of energy and contain the detachment of portions of the structure during or immediately after the occurrence of an exceptional event, such as an explosion or an earthquake. All resin layers are integrally connected to the strong structure of the reinforcement structure where the fibre, which has high ultimate tensile strength but modest elongation values, in the order of 1-3%. Therefore, an impulsive destructive events, such as the one due to seismic shocks, of such intensity as to break the fibre, causes the simultaneous tearing of the fibres and of the resins anchored to them by impregnation, and hence of the connection to the structure subjected to the intervention.